The present invention pertains to the telephone network and in particular, to the local loop that extends from the subscriber sites to the Central Office (CO) serving those sites. The present invention specifically concerns a method and apparatus for allowing the copper twisted pair at individual subscriber sites, to reappear at the central office and allows these subscribers within a specified proximity to be interconnected in the form of a Local Area Network (LAN).
There are a number of ways to enhance the performance of an unshielded twisted pair of wires that service a customer with voice band service. One could increase the present information rate or move to more sophisticated modulation schemes but ultimately the biggest performance leap is determined by the ability to adjust or fine tune the integrity of the physical layer. In some cases tuning the integrity of that layer (i.e. twisted copper pair) is plainly not practical. Since all telephony customers are ultimately connected to the central office (CO) by way of the twisted pair that is in their respective homes, it is not a new concept to have a group of customers"" lines all terminate into a xe2x80x9cvaultxe2x80x9d. From this vault a simple connection is made ultimately back to the CO. This concept is very straightforward as long as the type of service and the modularity of the physical layer are constant.
With the advent of technologies like xDSL (a family of generic Digital Subscriber Lines), the mix has changed a bit. Now the twisted pair that used to be for voice band communications is being pushed to provide more than 64-kilobit service. Even more, multiple combinations of twisted pair can be used to provide the end user with upwards of 20 Megabits/second. Squeezing the performance out of the twisted pair does not come without a downside. The provider of the service will, in most cases, still be held accountable for the traffic that the twisted pair was originally designed for. Careful planning must be taken not to design without regard to POTS (Plain Old Telephone Service) service. Recent efforts have been made in systems that employ the Digital Subscriber Line Access Multiplexers (DSLAMs) to provide low frequency filtering to insure that POTS traffic is not lost in the high rate xDSL traffic. There are inefficiencies associated with the DSLAM and with filtering as discussed below.
There are existing systems that create Local Area Networks (LANs) but these system are expensive to implement since they require the installation of a transmission media which has a much higher bandwidth than the copper pair, between the central office and the subscriber premise. There are several local access strategies and architectures deployed by LECs, cable service providers (CSPs), and digital broadcast TV distributors. All have some inefficiency and are generally costly.
The present embodiment of the invention provides a novel means for connecting a subscriber to a local area network (LAN) by extending the copper wire in a subscriber loop, to a point of presence (POP) in the serving network, by a virtual twisted pair and by allowing the subscribers within a loop to inter-connect and operate as a LAN. The present invention also allows the easy creation of a much larger network by providing connectivity to other subscriber loops and service providers offering Internet access. The present embodiment of the invention may be used to carry any traffic that requires high bandwidth.
The present invention further provides a tremendous advantage in the existing telephone network by using the current infrastructure and enhancing it to allow the copper pair at each subscriber site to reappear at the central office (CO) with minimum use of the infra structure of the existing network. It also allows users within a specified region to be interconnected and operate as a LAN.
The value of providing a point of presence (POP) for accessing a subscriber with minimum action of the Local Exchange Carrier (LEC) is very important. There are several local access strategies and architectures deployed by LECs, cable service providers (CSPs), and digital broadcast TV distributors. This proposal herein addresses two primary configurations 1) Direct connection between customer and central office (CO) and 2) Proposals that involve cable, including HFC, and telephony distribution concentrated at an intermediate collection point (vault) prior to xe2x80x9cbundlingxe2x80x9d all branches onto a high bandwidth trunk which then connects to a CO.
In another sense the invention is embodied as a system for enabling a local loop partial bypass to interact with a plurality of networks through an interface or linking circuitry joining the loop to a destination/recipient-processing network. Originating signals normally applied to the local loop are concentrated by multiplexing onto a common destination network, such as a (LAN). Packet signals and switched signals are identified and handled separately by different modems during processing and transmission by the loop bypass to the destination/recipient network Signals are provide transmission paths should the modems be bypassed.
While the connecting links are identified, in the illustrative embodiment as twisted pair or optical links, links such as cable/coax and wireless RF may also be used without departing from the spirit and scope of the invention. The principals of the invention may also be applied in wireless systems as well.